(C#) RSA Sign using Base64 Private Key

Signs a string using a non-encrypted RSA private key in base64 encoding. Returns the RSA signature as a base64 string.

Note: This example requires Chilkat v11.0.0 or greater.

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bool success = false;

// This requires the Chilkat API to have been previously unlocked.
// See Global Unlock Sample for sample code.

Chilkat.PrivateKey privKey = new Chilkat.PrivateKey();

Chilkat.StringBuilder sbPem = new Chilkat.StringBuilder();
sbPem.AppendLine("-----BEGIN RSA PRIVATE KEY-----",true);
sbPem.AppendLine("MIIC .... j5A==",true);
sbPem.AppendLine("-----END RSA PRIVATE KEY-----",true);

success = privKey.LoadPem(sbPem.GetAsString());
if (success == false) {
    Debug.WriteLine(privKey.LastErrorText);
    return;
}

Chilkat.Rsa rsa = new Chilkat.Rsa();

success = rsa.UsePrivateKey(privKey);
if (success == false) {
    Debug.WriteLine(rsa.LastErrorText);
    return;
}

Chilkat.BinData bd = new Chilkat.BinData();
bd.AppendString("12345678","utf-8");

success = rsa.SignRawBd(bd);
if (success == false) {
    Debug.WriteLine(rsa.LastErrorText);
    return;
}

// Get the base64 RSA signature.
Debug.WriteLine(bd.GetEncoded("base64"));

success = rsa.VerifyRawBd(bd);
if (success == false) {
    Debug.WriteLine(rsa.LastErrorText);
    return;
}

string strOriginal = bd.GetString("utf-8");
Debug.WriteLine(strOriginal);